This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. Ultrafast time-resolved Laue diffraction at atomic resolution of geometry changes on photoexcitation. A binuclear rhodium complex and several photosensitizer-dye crystals with short (sub-microsecond) lifetimes are to be measured. This will be the first time that submicrosecond diffraction measurements at atomimc resolution will be made.